/*
 * Copyright 2020 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package cc.siyecao.mapper.provider.defaults;

import cc.siyecao.mapper.provider.entity.EntityTable;
import cc.siyecao.mapper.provider.entity.EntityTableFactory;

import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

/**
 * 支持缓存实体类信息的方法
 *
 * @author liuzh
 */
public class CachingEntityTableFactory implements EntityTableFactory {
    /**
     * 缓存实体类信息
     */
    private final Map<Class<?>, EntityTable> ENTITY_CLASS_MAP = new ConcurrentHashMap<>();

    @Override
    public EntityTable createEntityTable(Class<?> entityClass, Chain chain) {
        if (ENTITY_CLASS_MAP.get( entityClass ) == null) {
            synchronized (entityClass) {
                if (ENTITY_CLASS_MAP.get( entityClass ) == null) {
                    EntityTable entityTable = chain.createEntityTable( entityClass );
                    if (entityTable != null) {
                        ENTITY_CLASS_MAP.put( entityClass, entityTable );
                    } else {
                        return null;
                    }
                }
            }
        }
        return ENTITY_CLASS_MAP.get( entityClass );
    }

    @Override
    public int getOrder() {
        return Integer.MAX_VALUE;
    }
}
